SWAP Streszczenie raportu

Semantic web and sail main memory implementation

Sesame is an architecture that allows persistent storage of RDF data and schema information and subsequent querying of that information. For persistent storage of RDF data, Sesame needs a scalable repository. Naturally, a Data Base Management System (DBMS) comes to mind, as these have been used for decades for storing large quantities of data.

As we would like to keep Sesame DBMS-independent, all DBMS-specific code is concentrated in a single architectural layer of Sesame: the Storage And Inference Layer (SAIL). This SAIL is an application programming interface (API) that offers RDFspecific methods to its clients and translates these methods to calls to its specific DBMS.

For some applications such as P2P information sharing, the use of a DBMS as a storage device is not a good option because of the administrative overhead created by the database. In case of rather small data sets and the need for fast response time, a lightweight solution is preferable.

In the SWAP project an in memory storage for RDF data has been developed as a lightweight solution. The repository implementation can be accessed via the SAIL API and is part of the official Sesame distribution. The implementation has been show to outperform the database-based implementations by orders of magnitude wrt. response time and caused a significant speedup in the exchange of RDF data in the SWAPSTER system.

The development of the in memory storage makes Sesame a light weight storage infrastructure that is better suited for distributed and mobile applications.